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Pentium III 850E overclocking question?

I just purchased a Boxed Pentium III 850E SECC2 CPU with fan and heatsink attached and I would like to see how far I can overclock this baby. Can anyone tell which multiplier/bus speeds combinations I should start out with or a web site that has this information? I have an ABIT BE6 motherboard with 256 MB of PC100 RAM.

Cyberman, that PIII 850E is sort middle of the road for overclocking. It's high multiplier may end up placing the 133MHz FSB mark out of reach with aircooling. However, with the right mix of video card + PCI devices you still stand a good chance of hitting the GHz mark. 118MHz FSB speed will put you at 1002MHz.

Unlike most PIII 600Es which will easily run at 133MHz FSB for 800MHz I have my doubts that the 850 will do 133MHz for 1130MHz on air cooling.

133MHz FSB is the 'silver' bullet of overclocking because it places the PCI devices back at spec-ed levels with a BX board (AGP & PCI with a VIA 133ProA board)and helps significantly with stability when overclocked. Your PC-100 SDRAM is your first issue. Most gneric PC-100 SDRAM will fail at FSB speeds of 124MHz and beyond so that will be one of your limitations to a high clock speed. With only the 2/3 AGP divisor on the BX mobo (1/2 is avail on the VIA Pro 133 A) you have to have to be careful which video cards you use. The Matrox G400, GeForce SDR/DDR, the GeForce GTS and some Voodoo3 cards are your only bets for high AGP bus speed tolerance.

If you have all your cards stacked right you will hit the GHz otherwise be happy with 952 @ 112MHz FSB (8.5 x 112MHz) if you don't want to do more shopping. The 8.5 multiplier is locked so you can only adjust the FSB speed

Really appreciate your help. So far I can only get it to run stable at 105 MHz fsb which only brings me up to 893 MHz. At 110 MHz 3DMark 2000 starts to act up. Since the specs of my motherboard says I must use only FSB 100 I can not get the benefits of 133 MHz. I was contemplating purchasing the Alpha P3125 Cooler to see if I could at least remain stable at 110 MHz FSB. This would at least get me to 935 MHZ. I just don't know if my lockups at this speed are due to the heat buildup on my CPU or my other components. If they are due to other components then cooling the CPU alone would not help much.

one stick is supposed to be more stable than two but my guess is you like having more memory , you will definitely have problems with heat, i highly suggest a better HSF...now that i know the effects of heat in a computer system i will never again build one without a good HSF...the alphas rock, expensive but...ive gotten a [email protected]+ (limited by HDD)

why do you have two voodoo2's?

what hdd interfaces? scsi or ide?

3dmark2000 stinks...i can run anything but that at 140+ fsb...it falls back to win

S_Klass is right, I still have a lot of old games require the Voodoos, such as the GL versions of Quake (GLQUAKE). Anyway, yes I did flash my BIOS when I upgraded to the 850 CPU. I do not think I am going to bother upgrading the heatsink and fan, the risks to me are not worth the rewards. Besides I am happy enough with my current speed. Quake 3 Arena and Need for Speed Porsche Unleashed are absolutely gorgeous at 1600 x 1200 and quite playable at these resolutions.

Phily - Yeah, I love it too, it basically allows you to run most games at the highest resolution possible, although you do need a lot of CPU power to handle it (800 MHz or better). What do you use for benchmarking if you don't use 3D Mark 2000? What CPU do you have and what is your FPS for Quake 3 with everything on at 1600 X 1200? By the way in case you have not tried them yet I tried out the new Nvidia Beta drivers version 5.33 and they were slower than the 5.32 at least with 3D Mark 2000, no differece in Quake 3, so I went back to 5.32, just thought you might want to know.